body {
    height: 100%;
    background-image: url('../image/bg.jpg');
}
.form-register {
    width: 100%;
    max-width: 400px;
    padding: 15px;
    margin: 0 auto;
}
.form-group {
    margin-bottom: 5px;
}
form a{
    display: inline-block;
    margin-top:25px;
    line-height: 10px;
}